基于WASP模型的桃林口水库水质模拟研究

为掌握秦皇岛桃林口水库未来水质变化的状况,本文选取总磷(TP)、硝酸盐氮(NO3-N)、氨氮(NH3-N)、高锰酸盐指数(CODMn)和溶解氧(DO)等5项水质指标,基于2014~2015年水源站和出库站两个监测站的5项水质指标的监测数据,确定WASP模型的参数;再根据水源站2016、2017年5项水质指标来预测出库站的水质情况。研究结果表明:该WASP模型对5项水质指标的模拟值的判定系数R2均大于0.7,相关系数r均大于0.83;各项水质指标的实测值与模拟值的相对误差一般低于10%。WASP模拟效果良好,可以运用到桃林口水库的预测预警系统中和水库水质预测与管理的工作中,同时为秦皇岛市青龙县水环境保护与管理工作提供决策性参考与依据。

Quantifying the impacts of emissions and meteorology on the interannual variations of air pollutants in major Chinese cities from 2015 to 2021

Air pollutant concentration is a function of emission rates and meteorology.To accurately evaluate the effect of control measures,the meteorological covariate must be corrected from the observations.This study quantified the impacts of emission abatement and meteorological condition on the interannual variations of SO_(2),NO_(2),CO,O_(3),PM_(10) and PM_(2.5) concentrations in 31 major Chinese cities using an optimized machine learning-based meteorological normalization technique.Overall,the annual average concentrations of SO_(2),NO_(2),CO,PM_(10)and PM_(2.5)were reduced by 86%,51%,99%,86% and 88%from 2015 to 2020,respectively,in the studied cities,attributable to their emission reductions.However,the concentration of O_(3) was found with no significant decrease with the reduction of precursors.Emission abatement notably improved air quality between 2015 and 2018.Such a decline in emissions tended to progressively slow down since 2018.Overall,the meteorological conditions in 2016–2017 and 2018–2019 were unfavorable for a better air quality,while it became favorable in 2020–2021.Specifically,emission abatement in 2021 further lowered the concentrations of SO_(2),NO_(2),CO,and PM_(2.5),while the emission of PM_(10) increased.And changes in precursors emissions worsened O_(3) air quality.To meet the demand of improving air quality,more aggressive abatement measures need to be formulated to synergistically reduce NOx,volatile organic compounds,and coarse particles.

Occurrence and distribution of antibiotic resistance genes in the sediments of the East China Sea bays

The coastal area of the East China Sea has experienced rapid urbanization and industrialization in China since 1980 s, resulting in severe pollution of its environments.Antibiotic resistance genes(ARGs) are regarded as a kind of emerging pollutant with potential high risk. The sediment samples were collected from Hangzhou Bay(HB),Xiangshan Bay(XB), and Taizhou Bay(TB) to investigate the spatial occurrence and distribution of 27 ARGs and class I integron–integrase gene(intI1) in the coastal area of the East China Sea. The PCR results showed the frequent presence of 11 ARGs and intI1 in the sediments of the three bays. The qPCR results further showed that sulfonamide resistance was the most prevalent ARG type and antibiotic target replacement and protection were the most important resistance mechanisms in the sediments. Regarding the subtype of ARGs, sulI, tetW, and dfrA13 were the most abundant ARGs, in which sulI was higher in TB(based on both the absolute and relative abundances) and dfrA13 was higher in HB(based on the relative abundances). The network analysis revealed that intI1 had significant correlations with tetC, sulI, sulII, and blaPSE-1. Oil was the key connected factor, which had positive connections with sulI, sulII, and blaPSE-1. In addition, the joint effect of heavy metals and nutrients & organic pollutants might be crucial for the fate of ARGs in the coastal sediments.

Temporal and spatial changes of microbial community in an industrial effluent receiving area in Hangzhou Bay

Anthropogenic activities usually contaminate water environments, and have led to the eutrophication of many estuaries and shifts in microbial communities. In this study, the temporal and spatial changes of the microbial community in an industrial effluent receiving area in Hangzhou Bay were investigated by 454 pyrosequencing. The bacterial community showed higher richness and biodiversity than the archaeal community in all sediments. Proteobacteria dominated in the bacterial communities of all the samples; Marine_Group_Ⅰ and Methanomicrobia were the two dominant archaeal classes in the effluent receiving area. PCoA and AMOVA revealed strong seasonal but minor spatial changes in both bacterial and archaeal communities in the sediments. The seasonal changes of the bacterial community were less significant than those of the archaeal community, which mainly consisted of fluctuations in abundance of a large proportion of longstanding species rather than the appearance and disappearance of major archaeal species. Temperature was found to positively correlate with the dominant bacteria, Betaproteobacteria, and negatively correlate with the dominant archaea,Marine_Group_Ⅰ; and might be the primary driving force for the seasonal variation of the microbial community.

Identifying human-induced influence on microbial community:A comparative study in the effluent-receiving areas in Hangzhou Bay

Microbial community structure is afiected by both natural processes and human activities.In coastal area,anthropegenetic activity can usually lead to the discharge of the effluent from wastewater treatment plant(WWTP)to sea,and thus the water quality chronically turns worse and marine ecosystem becomes unhealthy.Microorganisms play key roles in pollutants degradation and ecological restoration;however,there are few studies about how the WWTP effluent disposal influences coastal microbial communities.In this study,sediment samples were collected from two WWTP effluentreceiving areas(abbreviated as JX and SY)in Hangzhou Bay.First,based on the high-throughput sequencing of 16S rRNA gene,microbial community structure was analyzed.Secondly,several statistical analyses were conducted to reveal the microbial community characteristics in response to the effluent disposal.Using PCoA,the significant difference of in microbial community structure was determined between JX and SY;using RDA,water COD and temperature,and sediment available phosphate and ammonia nitrogen were identified as the key environmental factors for the community difference;using LDA effect size analysis,the most distinctive microbes were found and their correlations with environmental factors were investigated;and according to detrended beta-nearesttaxon-index,the sediment microbial communities were found to follow"niche theory".An interesting and important finding was that in SY that received more and toxic COD,many distinctive microbes were related to the groups that were capable of degrading toxic organic pollutants.This study provides a clear illustration of eco-environmental deterioration under the long-term human pressure from the view of microbial ecology.

Antibiotic resistome mostly relates to bacterial taxonomy along a suburban transmission chain

Antibiotic resistance genes comprising antibiotic resistome are of great concern due to their increase in the environment.Recent evidence of shared resistomes between soils and animal husbandry has imposed potential risks to human health.However,the correlation between a given community’s resistome and bacterial taxonomic composition is controversial.Here,a transmission chain of resistomes from swine manure to compost and compost-amended soil were analyzed in five suburban areas of Beijing,China,with unamended agricultural soils as control soils.Antibiotic resistomes and bacterial taxonomic compositions were distinct between(I)manure and compost;and(II)compost-amended and control soils.In manure,compost,and compost-amended soils,theβ-diversity of the resistome and bacterial taxonomic composition was significantly correlated,while no correlation was detected in control soils.Bacterial taxonomic composition explained 36.0%of total variations of the resistome composition,much higher than environmental factors.Together,those results demonstrated that antibiotic resistome was closely related to bacterial taxonomic composition along the suburban transmission chain.